New ürleans m ('Xteftiivoly [r(6ud ] botli on the sido nf tho Mísm-í pi and 1 bh at of Lake Poiicliartrmn. Rodaubts Lf ;i foni)id;i!i!o cliaratifV hav bcii khrovvn ui), nnd ht-a-.-y uüi.mii mounled ut every ixposed pirt. A;a thetruth probablv is, thnt tho relieN rulv moro upoii ihe ostensivo f'orlificntiorm at thp Rigolojls and lbofce defenditig tho Mississinpi Rivëf fiear ts outlJt, f hun they dn u:i'iii tho oartiiwüi !.s 'iikI biitteriea lurrrïuriding thé pny. Porit iuevident t'tj :it should' oor 1 tiHa iuéeeed in aseenling iliu MiásiisMÍppi t(, the city, they 00 u ld éiisily reduce tho placo bv 11 severo boiil)Mi]inent. Stiil it is n"l.r probablo ilint even shouhi succmê attend tho preliininnry inpvementé il the fiuet, thuy wouldstill h:ive a stubborn resista ncé to overeóme, as I General Mnn.field Lovd is in cnmniuinl, vyith a forcé o] no; less than tivo thuusund men. Burieles, pollino, of steam'-ram notoriety, 'm somewbere in ihe neigbborhpocl of ihe city, and lias i prúbablj' ; " U-w rnoro " rebel gunboaíá on hand with whioh to deétroy our flotilla. THE RIGOI.HTS. TI10 secoml espedition which kTt Snip Island fór New Orlen ns is reprorted to have taket) t)t 3 direct on of Lake Poachartrain. In that case the ohannelu called the Eigolota woukl havo to be passed through, betore entering the lako. Novv, nn islaud :it tho inouth of ihe lake forms two ehannels, both sides of which are hoavilv forti 6ed. On the island itself' stands Forts Pike and Macomb. lf, as hoe boen reported, the formen, is in o;ir possession, one great obstaele to the advanup, is removed. fStül the latter and the battorios on ihe opposite shore would"have to be BÜeoced before a successfnl ad vanee of the floot eould be nsured.- Assuming, however, that tho forts relerred to havo been reduced, the reducción of the city in that caso would beuome a mere qnestion of time. Although fortifieationa exist along the boundary ot ihe lake on the gfde bj whioh the city can be approached, yet a bombardment a ia Port Honry would saon silence the rebel batteries and inBUre a direct and attack. Lakeport is distant frorn New Orleans about ton , miles; Carr .ton only six. BXPEDITIO.M ll TIUi MISS1SSIPPI. But the rnajn aitaok, in all probability, haa ben made by vvay of the MiesisHippi River. Indeed, the expedition befpre Fort Jackson confeisls öf at least fifty-íour caile, with a Very heavy arraanient. TI10 first formidable buttorios to bo encountered aro thoso callod Forts Jackson and St. Phillip situated op paite each 01 her and Gomtnanding an enire rango oí' tho stioani. These torts have an firmament of one hundred and seventy heavy guns, consisting.ihitjflj of 68-poand rifled csanoon. The navigation ói the river is stopped by a dam, distant about a quai:ter of a in!lö froin the fvrts. Prpm thia point to New Orlsnns the banks oi the Mississij.pi are lined with a constant 6uceesnion of earihworlcü and stono fortific-.liotis, the most formidable of the latter description beingcfdled Point a la Hucha; Woodvilla and Loon.